Layers of bottom sediment reveal secrets of environmental changes in the Baltic Sea

By studying the seabed, we can obtain information about environmental changes in the Baltic Sea and the factors affecting them over several thousand years.

The bottom sediment of the Baltic Sea is being studied in a Finnish-led research project as part of the joint European BONUS research programme.

“The area of research extends from the marine environment of Skagerrak to the almost fresh water of the Northern Baltic Sea. By studying the bottom sediment, we’re aiming to obtain information on the natural variations in the environmental conditions of the Baltic Sea and on the effect of human activity on environmental changes,” says Research Professor Aarno Kotilainen of the Geological Survey of Finland, who is coordinating the project.

Climatic conditions affect the temperature, salinity and changes of current in the Baltic Sea. They regulate such things as the salt water pulses that occasionally flow from the North Sea to the Baltic Sea. The eco-system and environmental conditions of the Baltic Sea are influenced both by local climate and that of the North-East Atlantic. This project coordinated by the Geological Survey of Finland is studying Baltic surface- and deep water conditions and their temporal variation, by looking at the layers of sediment on the seabed, using multivariate analysis.

By modelling, the project also aims to forecast the effects of climate change on the Baltic Sea. “A deeper understanding of the factors affecting the long-term changes in the Baltic Sea and of possible future changes is important. This knowledge is needed to support planning for the sustainable use of the marine regions and in preparation for the effects of climate change,” summarises Professor Kotilainen. In addition to the Geological Survey of Finland and the Department of Geology at the University of Helsinki, other participants in the research come from Russia, Germany, Denmark, Sweden, Poland and Norway.

Research funding organisations from the nine Baltic Sea nations are behind the BONUS programme, which was launched at the beginning of this year. The study is also being funded by the EU Commission.

The Finnish funding organisation is the Academy of Finland. At the first stage of the research programme, decisions were made to fund 16 research projects with a total of 22 million euros, with more than 100 research institutes and universities from the Baltic Sea countries taking part. Finland is coordinating four of these projects. Total project funding will be approximately 60 million euros between 2010 and 2016.